Browsing by Subject "Minimally invasive surgery"

Now showing 1 - 3 of 3

Design and evaluation of a novel in-vivo laparoscope cleaning device
(2019-02-14) Idelson, Christopher Robert; Rylander, Christopher Grady, 1978-; Uecker, John M; Crawford, Richard H; Nichols, Steven P; Williams-Brown, Marian Yvette
Laparoscopy is a method of minimally invasive surgery that is used in millions of procedures annually around the globe. Its usage trend is rising rapidly due to more favorable medical and monetary outcomes, especially when compared to open-surgery. One issue in laparoscopic procedures arises when the laparoscope lens becomes obstructed via condensation, bodily fluids, or tissue matter/residue. Currently, cleaning the laparoscope requires removing the scope from the body, wiping it on a sponge/cloth, and usually applying anti-condensation solution to the lens before reinserting the scope into the body. This scope cleaning process generates concerns related to medical and economic outcomes, with shows statistical correlation to higher rates of complications and post-surgical site infections with extended times under anesthesia. The ability to clean a laparoscope quickly and effectively inside the body stands to improve medical and monetary outcomes for numerous stakeholders. Current technologies show minimal adoption due to problems surrounding efficacy, compatibility, etc. This dissertation describes the analysis of customer needs relating to this medical issue in addition to the design and evaluation of a novel in-vivo laparoscope cleaning device to address the problem. Also included is additional discussion surrounding regulatory considerations of said device
Design of two novel specimen retrieval devices : shielded blade and laparoscopic extraction forceps
(2024-05) Whitman, Alexander Thomas ; Tunnell, James W.; Byron Wilson; John Uecker
Two distinct and novel devices for the improvement of specimen retrieval associated with minimal invasive surgery (MIS) are proposed. Specimen retrieval, as an act of tissue removal, has proven to be a source of observed clinical need that is validated by peer-reviewed literature as well as the anecdotal report of expert clinicians trained to perform tissue excision as a component of practice. Frequently, the tissues excised as part of routine MIS are larger than the necessary port sites through which the clinician operates. These tissues often require pathological analysis which necessitates the preservation of tissue margins during extraction. Existing methodologies for removal require incision extension or morcellation at the expense of patient recovery and decimation of tissue, respectively. The first device, Shielded Blade, serves as an aid for the extraction process by limiting the incision size necessary for removal and eliminating the risk of containment bag rupture. The second device, Laparoscopic Extraction Forceps, enables the extraction of large specimens through narrow incisions while maintaining tissue margin integrity via a discrete segmentation process. The specimen is deconstructed such that the whole tissue can be accurately analyzed post-extraction. This thesis details the investigation, design, and evaluation of both prototypes including qualitative feedback from expert physicians. An experimental study comparing the Laparoscopic Extraction Forceps device to morcellation and whole-specimen extraction was completed.
Developing a novel distributed fiber optic shape sensor for continuum manipulators
(2022-08-18) Nguyen, Nathan K.; Fey, Nicholas Phillip; Alambeigi, Farshid
In recent years, Fiber Bragg Grating (FBG) optical fibers have gained popularity to be used for shape sensing (SS) of continuum manipulators (CMs) developed for various minimally invasive surgeries. Despite their benefits, arduous and costly fabrication procedure together with the limited and discrete sensing nodes on each fiber are some of the main shortcomings of FBG-based SS of CMs. Aiming at addressing these challenges and leveraging the Optical Frequency Domain Reflectometry (OFDR) technology, I propose a design and evaluate the performance for a shape sensing assembly (SSA) that consists of solely one distributed fiber optic sensor and a flat Nitinol wire. The proposed SSA and fabrication procedure can collectively address the mentioned drawbacks of FBG-based SSAs (i) by continuously measuring the strain along the length of fiber at a high resolution, and (ii) offering a simple, cost-efficient, and repeatable manufacturing process that reduces the assembly time and improves accuracy. To evaluate performance, the SSA was subjected to three separate bending experiments. In free-bending, the SSA resulted in an average tip error of 0.657 mm and shape error of 0.549 mm. For S-bending, the average tip error and shape error are 1.840 mm and 0.846 mm, respectively. In obstacle bending, the SSA achieved an average tip error of 5.292 mm and average shape error of 2.711 mm.